The present invention generally relates to a bearing arrangement and more particularly to a bearing arrangement using few assembly bearings and particularly adapted for use with a three cylinder engine.
German Published, Unexamined Patent Application (DE-OS) 33 31 417 discloses a bearing arrangement for a drive assembly of a motor vehicle which has three bearings and two torque supports, two opposite bearings being arranged in the area of a main inertia axis extending through the center of gravity of the assembly. Because of the additional bearings provided next to the inertia axis and the torque supports, this type of an arrangement requires high structural expenditures, and a coordination of the bearings with respect to one another corresponding to their function which requires relatively high expenditures because the bearing sites are located far apart and at a distance with respect to the axis of inertia
It is an object of the present invention to provide a bearing arrangement utilizing a small number of assembly bearings which compensates for the special vibration behavior of a three-cylinder engine; i.e., they are located in low-vibration areas and, each separately can be adapted to a main load type.
Main advantages achieved by preferred embodiments of the present invention are that, as a result of the arrangement of a central bearing, which carries almost the complete static load, and a torque support in the low-vibration area, very low vibration levels occur at the bearing elements which essentially hold the assembly when the engine is standing as well as when subjected to a load.
With the single central bearing arranged underneath the engine, a vertical support base for the engine torque can be achieved that is as large as possible, with respect to the torque support fastened at a cylinder head of the engine. As a result the forces to be supported are so low that the vehicle does not experience any unpleasant longitudinal bucking or vibrational shaking caused by load changes.
For vibration-technological reasons, the rubber elements are arranged as closely to the assembly as possible in order to avoid increases of vibration due to long lever arms and resonances of the bearing supports. For the supporting of the torque, the geometry of the engine is utilized; i.e., almost the entire overall height of the engine.
The support bearing is arranged at the front end of the engine because, in comparison to the front end of the transmission, lower vibration levels occur at the front of the engine in the case of a three-cylinder engine and, in addition, no transmission noises are transmitted.
The stiffness of the bearing element at the support bearing, in vertical as well as in driving direction, may be designed to be very soft, since the support load is very low and it does not have to support any torque. Since the center of gravity of the assembly is located almost in one plane with the central bearing and the torque support, no significant inertial forces occur at the support bearing during acceleration and deceleration.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.